Synthetic materials for water drainage systems

ABSTRACT

Synthetic rocks are used as a substitute for natural gravel to fill in a water drainage trench. The synthetic rocks may be used around perforated drain tiles in a basement water drainage system, or they may be used without such tile. The synthetic rocks may be of a size and shape that mimics the natural rock they replace, but they are preferably significantly lighter in weight. The synthetic rocks may alternatively be tubular or cubic shaped, for example, and may include one or more lumens or other passageways to facilitate the flow of water through and/or around the rocks. The synthetic rocks may be provided in mesh bags to facilitate placement in a water drainage trench.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.12/476,762, filed Jun. 2, 2009, which is a continuation of U.S. patentapplication Ser. No. 11/409,386, filed Apr. 21, 2006, now U.S. Pat. No.7,553,104, which is a continuation-in-part of U.S. patent applicationSer. No. 11/258,252, filed Oct. 25, 2005, all of which are herebyincorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates generally to materials and methods for usein water drainage systems.

BACKGROUND TO THE INVENTION

The use of drainage trenches to direct water away from a building, andthus to prevent water from seeping into the building, has been known formany years. In some cases perforated or slotted drain tiles are used inthe trenches, with the trench being provided around the inside and/oroutside perimeter of a building to form a pipe line which relieveshydrostatic pressure by collecting and diverting water away from thebuilding, such as to a sump pump or a drainage field. Such systems arefrequently referred to as French drain tile systems.

The drain tiles typically comprise perforated or slotted pipe sectionswith sufficient perforations or slots to collect and divert water. Thetiles are used to at least partially fill the trench and keep dirt anddebris from filling the trench and restricting the flow of water. Thetiles may also help support a covering material, such as concrete oranother flooring material.

In some cases the tiles are positioned in a bed of river rock, gravel orcrushed stone (referred to collectively in this disclosure as naturalgravel, rock, or stone), which allows water to flow into the tiles andkeeps dirt from clogging the perforations/slots. The gravel alsoprovides a supporting substrate for concrete, etc., that may be added tocover the drain tiles from above.

In other water drainage systems gravel may be used to facilitate waterflow even when perforated drain tiles are not used. In such systemsanother channel material may be used, or the trench may be filled onlywith gravel.

While the use of gravel to surround the drain tile provides advantagesin terms of allowing good water flow and the ability to hold the tile inplace, it also has disadvantages. For example, because the amount ofgravel used in a particular job is large, heavy equipment such as dumptrucks and front loaders are generally required to transport and handlethe stone. In addition, transporting the gravel around the job site(e.g., into a basement) requires substantial physical labor and addssignificant cost to the job.

Similarly, the use of gravel in tile-free systems also hasdisadvantages, including difficulty in transporting, storing, and usingthe gravel, as well as its propensity for introducing dirt or othercontaminants to the drain area.

A need therefore exists for materials and methods for use in waterdrainage systems when it is desired to avoid the disadvantages ofnatural gravel. The present invention addresses that need.

SUMMARY OF THE INVENTION

Briefly describing one aspect of the present invention, there isprovided a method of facilitating the flow of water in a water drainagesystem by providing a water flow path that is at least partly filledwith a lightweight, synthetic filler material such as synthetic rocks.In another aspect of the invention a synthetic filler material is usedto fill in around perforated drain tiles in a water removal system. Thesynthetic filler material may comprise a plurality of individual piecesthat optionally include one or more passageways therethrough tofacilitate the flow of water through the material. Relatively largenumbers of the synthetic filler pieces may be enclosed in mesh bags tofacilitate the handling of the material.

DESCRIPTION OF THE DRAWINGS

FIG. 1 shows one embodiment of a drainage trench with synthetic rock andperforated tile.

FIG. 2 shows one embodiment of a synthetic rock that may be used in themethods of the present invention.

FIG. 3 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 4 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 5 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 6 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 7 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 8 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 9 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 10 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 11 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 12 illustrates one method of providing a drainage trench withsynthetic rock and perforated tile.

FIG. 13 shows one method of using synthetic rocks to replace naturalrock to fill in around drainage tile.

FIG. 14 shows a section of semi-rigid material overlaying synthetic rocksurrounding drain tile in one embodiment of the present invention.

FIG. 15 shows another view of the embodiment of FIG. 14.

FIG. 16 shows another embodiment of the synthetic rocks that may be usedin the methods of the present invention.

FIG. 17 shows the synthetic rocks of the present invention in mesh bags,such as may be used in a water flow path that does not include draintile.

DETAILED DESCRIPTION OF THE INVENTION

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to certain embodiments andspecific language will be used to describe the same. It willnevertheless be understood that no limitation of the scope of theinvention is thereby intended, such alterations and furthermodifications of the illustrated embodiments being contemplated as wouldnormally occur to one skilled in the art to which the invention relates.

As indicated above, one aspect of the present invention relates to theuse of lightweight, synthetic rocks or pellets to fill in around alength of perforated drainage tile. In one preferred embodiment, thedrain tile is being used in a basement waterproofing system. Thesynthetic rocks support the drainage tile in a manner in which water isfree to flow into the tile. In the preferred embodiment mentioned above,the synthetic rocks also provide a substrate on which, for example,concrete may be poured to repair the floor. The synthetic rocks functionmuch as natural rock would in a similar environment, but are far easierto transport and install.

In another aspect of the invention synthetic rocks appropriate for usein water drainage systems are provided. Such rocks may be sized andshaped to at least partially fill a drainage trench without undulyrestricting the flow of water through the trench. In other aspects therocks may be sized and shaped to fill in around perforated drain tile.The synthetic rocks of the present invention may include one or moreopenings or passageways to facilitate the flow of water through a bed ofthe rocks.

In another aspect of the present invention, synthetic rocks are used toat least partially fill in a water flow path without unduly restrictingthe flow of water through the path. In such cases the synthetic rocksmay support concrete or another covering material, while still allowingthe free flow of water through the system. The method is particularlyuseful for covered water drainage systems.

As to the synthetic rocks that may be used in one or more aspects of theinvention, the synthetic rocks may be of substantially any shape andsize effective to fill in around a drainage tile, although syntheticrocks that simulate natural gravel are preferred for certainapplications. In some preferred embodiments the synthetic rocks may betubular shaped, such as is shown in FIGS. 13 through 16. Such tubularmembers may be referred to as mini-tubes. Synthetic rocks of differentshapes and/or sizes may be used together, and in some cases syntheticrocks may be used with natural rock. The synthetic rocks may function asa filler material to fill in around drainage tiles and to facilitate theflow of water into and through the tiles.

In some embodiments the synthetic rocks are generally tubular, while inother embodiments the synthetic rocks are cubic or pyramidal shaped. Insome embodiments the synthetic rocks are irregularly shaped, much asnatural rock is. The synthetic rocks need not replicate the look ofnatural rock, so long as the synthetic material can function generallyas natural rock would when used to fill in around train tiles.

In some embodiments the synthetic rocks have at least one hole (whichmay be referred to as an opening, an aperture, or a lumen) extendingthrough the rock to permit water to flow through, and not just around,the rock. In some preferred embodiments two, three or more holes areprovided through the synthetic rocks. In other embodiments the syntheticrocks have other passageways or open spaces to facilitate the flow ofwater around and/or through the rock.

In some preferred embodiments the largest dimension of the syntheticrocks is less than 2 inches, more preferably between 0.5 inches and 1.5inches, and most preferably between 0.75 inches and 1.25 inches. Inother preferred embodiments the synthetic rocks have a largest dimensionof less than 3 inches, more preferably between 0.5 and 2.5 inches, andmost preferably between 1.0 and 2.0 inches. In other embodiments thelargest dimension of the synthetic rocks is greater than 3 inches.

The synthetic rocks of the present invention are generally described asbeing “lightweight” because they are typically lighter than the naturalrock they replace. In some embodiments though, it is desired that thesynthetic rocks are heavy enough not to float in water, so that they aremore stable when used in a water flow path like a drainage trench. Inother embodiments it is desired to select and/or use synthetic rocksthat are “matched” to the flow characteristics of a particular waterflow path, i.e., to select synthetic rocks having a specific gravitythat is effective for use in a particular water flow path. For example,it may be desired to select synthetic rocks having a higher specificgravity for use in systems with a faster water flow, and to selectsynthetic rocks having a lower specific gravity for use in systems witha slower water flow.

In some embodiments the synthetic rocks have a specific gravity of lessthan 3.0, while in other embodiments the specific gravity is between 1.0and 3.0 or is between 1.0 and 2.0. In other embodiments, the syntheticrocks have a specific gravity of less than about 2.0, and alternativelya specific gravity of less than about 1.5. In still other embodiments,the synthetic rocks have a specific gravity of less than 1.0.

It is to be appreciated that the term “synthetic rock” as used hereinrefers to synthetic pieces of any type that may be used to replace anatural rock-like material in a water flow path—regardless of whetherthe synthetic piece closely mimics the shape of any natural material,and regardless of whether any natural material that is mimicked would bereferred to as a rock or a pellet or a stone, or some other name. Nodistinction is intended between synthetic rocks and synthetic pellets orsynthetic stones or synthetic gravel, etc. All such materials areintended to be included in the term synthetic rock.

Similarly, the synthetic pieces need not closely mimic the size and/orshape of any natural material, with synthetic pieces that are generallytubular in shape being particularly preferred for some applications.

The synthetic rocks may be made of any one or a combination of syntheticmaterials, and different materials may be used together in a singleapplication. In general though, the synthetic rocks are made of amaterial that is lightweight, yet strong enough to substitute fornatural gravel in waterproofing applications. Examples of syntheticmaterials include, but are not limited to, polyethylenes,polypropylenes, polystyrenes, polyvinyl chlorides, polyurethanes,polycarbonates, acrylics, polyethylene terephthalates, polyamides,polyesters, acrylonitrile butadiene styrenes, polyvinylidene chlorides,synthetic rubbers, etc.

In some embodiments the synthetic rocks are made of a material that doesnot absorb or retain water, and thereby keeps a drainage space, such asa crawl space, cleaner and less humid that comparable spaces in whichnatural rock or gravel is used.

The synthetic rocks of the present invention may be used with draintile, as indicated above. The drain tile may be perforated or slotteddrain tile such as is conventionally used in basement waterproofingapplications. Drain tile diameters are typically between about 2 and 6inches in diameter, and preferably about 4 inches in diameter, althoughlarger or smaller drainpipes may be used. While drain tiles are commonlyreferred to as perforated or slotted, the tiles may have opening ofvirtually any size and shape effective for allowing water to enterradially and flow through the tile. Moreover, the opening may bedispersed around the tile, or they may be concentrated on only one ormore sides, such as on the top portion of the tile when the tile is laidin a drainage trench.

For the purposes of this disclosure, the term “perforated drain tile” isunderstood to refer generally to all drain tiles, pipes, tubes,channels, etc., having perforations, slots, or other openings that allowwater to flow into the tile. Also, in this disclosure perforated draintile may alternatively be referred to as perforated drainpipe.

It is also to be appreciated that the term drain tile as used hereinrefers to any drain tile, pipe, channel, or tubing that may be used todirect a flow of water, such as in basement waterproofing applications.The drain tile, pipe or channel may be rigid or it may be flexible, andit may be provided in substantially any length and diameter appropriatefor a particular application. The tile may have substantially anycross-sectional shape, such as circular, rectangular, triangular, or anirregular shape.

To illustrate one method for practicing the invention, a drainage trench(alternatively referred to as a drainage channel or a drainage pathway)may be dug below the floor around the inside perimeter of a building.Alternatively, a channel or trench may be provided around the outsideperimeter of a building, or at other location desired to be protectedfrom water. As is known to the art, when a trench is dug inside anexisting structure it is common that a portion of the existing floor(generally concrete) will first need to be removed.

The trench may be of substantially any dimensions, but is commonly about6-18 inches deep and 6-18 inches wide, most commonly about 12 inchesdeep and 12 inches wide. The length is generally determined by the sizeof the area to be protected. In most cases the trench is dug to a depthnear, but not below, the depth of the bottom of the building foundation.

The drainpipe is laid in the trench. One, two, or more lengths of draintile may be laid adjacent to or on top of each other.

In some embodiments the drainpipe may be laid on top of a base layer ofsynthetic gravel. When a base layer of synthetic gravel is used, thebase layer is typically between 1 and 4 inches in depth.

Pins, nails, brackets, etc., may be used to hold the drainpipe in place.

Additional synthetic rock may be provided on top of and around thedrainpipe. This top layer of synthetic gravel may comprise the samesynthetic gravel that was used in the base layer (if a base layer wasused), or it may be different. The top layer is typically provided sothat it fills in around the drainpipe. The top layer may also cover thedrainpipe, most commonly to a depth of 1 to 4 inches.

Concrete or other solid flooring material may then be provided over thesynthetic rock to provide an appropriate floor. The concrete ispreferably poured to a depth of at least three or four inches.

Referring now to the drawings, FIG. 1 shows one embodiment of a drainagetrench with synthetic rock and perforated tile, as disclosed in oneaspect of the present invention. Trench 11 is provided in soil 12 afterremoving a portion of concrete floor 13. In the illustrated embodimenttrench 11 is adjacent footer 14 which supports foundation wall 15. Twolengths of perforated drain tile 16 are provided in trench 11. Syntheticrocks 17 are provided over drain tile 16. A section of vinyl Cove Mold18 overlays at least a portion of synthetic rocks 17. Replacementconcrete floor 19 is provided over synthetic rocks 17 and over vinylcove mold 18.

FIG. 2 shows one embodiment of a synthetic rock appropriate for use inthe present invention. Synthetic rock 20 includes side wall 22 andinterior walls 24 defining passageways 23 through the rock. Thedimensions of the illustrated embodiment may vary depending on thedesired use, but generally in one preferred embodiment the diameter “d”of the rock is between 0.5 inches and 2.0 inches and the length “1” ofthe rock is a similar size. The largest dimension of such rocks istherefore between about 0.5 inches and about 3 inches, with the largestdimension preferably being between about 0.7 inches and about 1.5inches.

FIG. 3 shows one embodiment of a synthetic rock appropriate for use inthe present invention. Synthetic rock 30 includes side wall 32 andinterior walls 34 defining passageways 33 through the rock.

FIG. 4 shows one embodiment of a synthetic rock appropriate for use inthe present invention. Synthetic rock 40 includes side wall 42 andinterior walls 44 defining passageways 43 through the rock.

FIG. 5 shows one embodiment of a synthetic rock appropriate for use inthe present invention. Synthetic rock 50 includes side wall 52 andinterior walls 54 defining passageways 53 and 55 through the rock.

FIG. 6 shows another embodiment of a synthetic rock appropriate for usein the present invention. Synthetic rock 60 includes side walls 64 andinterior walls 62 defining passageways 63 and 65 through the rock.

FIG. 7 shows another embodiment of a synthetic rock appropriate for usein the present invention. Synthetic rock 70 includes a combination ofrectangular and/or triangular and/or trapezoidal walls defining a shellthat may or may not include passageways through the rock.

FIG. 8 shows another embodiment of a synthetic rock appropriate for usein the present invention. Synthetic rock 80 again includes a combinationof rectangular and/or triangular and/or trapezoidal walls 82 cooperatingwith inner wall 84 to define passageways 83 through the rock.

FIG. 9 shows another embodiment of a synthetic rock appropriate for usein the present invention. Synthetic rock 90 again includes a combinationof rectangular and/or triangular and/or trapezoidal walls 92 cooperatingwith inner wall 94 to define passageways 93 and 95 through the rock.

FIG. 10 shows another embodiment of a synthetic rock appropriate for usein the present invention. Synthetic rock 100 again includes acombination of rectangular and triangular and/or trapezoidal wallscooperating with an inner wall to define a passageway 105 through therock.

FIGS. 11A and 11B illustrate another embodiment of a synthetic rockappropriate for use in the present invention. The synthetic rockincludes irregular shaped walls which may cooperate with an inner wallto define a passageway through the rock.

Illustrating now one method of practicing the present invention, asshown in FIG. 12 a drainage trench 121 may be dug below the floor 123around the inside perimeter of a building 125. A portion of the existingconcrete floor 123 has been removed. The illustrated trench is about 12inches deep and 12 inches wide.

One or two courses of drainpipe 126 may be laid in the trench.Additional lengths of drain tile may be laid end-to-end to connect thevarious pieces of drainpipe if necessary, or fewer, longer pieces ofdrainpipe may be used. Pins or nails 130 may be used to hold thedrainpipe in place. This is particularly helpful if the drain tile is alonger piece of lightweight plastic, and if the drain pipe is to be bentaround corners, etc.

Synthetic rock 127 may then be provided on top of and around thedrainpipe, preferably filling in around the drainpipe. The illustratedlayer of synthetic rock covers the drainpipe to a depth of about 3 or 4inches.

A semi-rigid supporting layer such as Cove Mold 128 may be used tooverlay at least a part of the synthetic rock. Concrete or other solidflooring material 129 may then be provided over the synthetic rock toprovide an appropriate floor. The concrete is preferably poured to adepth of at least three or four inches.

FIG. 13 shows a drainage trench with a portion of the trench beingfilled with drainpipe and natural rock, and a portion of the trenchbeing filled with drainpipe and synthetic rock. As can be seen from theillustration, the synthetic rock performs at least as well, whileproviding the advantages of being significantly easier to transport andinstall.

FIG. 14 shows a drainage trench that has been filled with drainpipe andsynthetic rock. In this embodiment the synthetic rock comprises 100pound psi ABS tubing that has been cut into sections approximately 1 to3 inches in length. Cove Mold has been used to cover a portion of thetrench before new concrete is poured. FIG. 15 shows another view of theembodiment of FIG. 14, particularly showing a finished corner before newconcrete is poured.

In other embodiments the synthetic rocks may be used even when no draintile is used. In such embodiments the drain tile may be used to at leastpartially fill in a drainage channel or trench to facilitate thelong-term flow of water through the trench. When synthetic rocks areprovided in the trench, dirt and debris will not fill the trench andrestrict the flow of water. The synthetic rocks allow a flow of waterthrough and around the rocks, thus facilitating the flow of water.Moreover, the synthetic rocks may support concrete or another floormaterial.

FIG. 16 shows synthetic rocks according to one preferred embodiment ofthe present invention. FIG. 17 shows another view of the synthetic rocksof FIG. 16, with the rocks being enclosed in a mesh bag to facilitatehandling and installation.

In one preferred embodiment the synthetic pieces of the presentinvention are provided in mesh bags to facilitate their handling anduse. Such mesh bags of synthetic rocks may be placed in water drainagetrenches around perforated drain tile, or they may be used even whendrain tile is not used. The bags of synthetic rock are particularlyeffective for facilitating water flow and for supporting a flooringmaterial that may be used to cover the rocks. The mesh bags facilitatethe handling of the synthetic pieces without unduly restricting the flowof water through the trench. The mesh bags also help control theplacement and movement of the synthetic pieces—both during and afterinstallation of the synthetic pieces.

The mesh bags may be of substantially any size and/or shape, with long,tubular bags effective for placement in a water drainage trench of thetype disclosed herein being particularly preferred. In some preferredembodiments the mesh bags are between four and twelve inches indiameter, and are between five and twenty-five feet in length. The bagsare preferably made of a water resistant material effective to preventdeterioration of the bags during long-term usage. The bags may besecured in place with fasteners, such as with heavy gauge poly vinylstraps or other fasteners located every three or four feet along thebag. Nails or other fasteners may also be used to secure the bags and/orits securing straps.

It is to be appreciated that the synthetic pieces of the presentinvention are particularly useful to facilitate the occasional flow ofwater in a drainage channel, such as in a water drainage system used toprotect a building. Such water drainage system may be provided below thelowest floor of a building, such as below or in a crawl space. In someembodiments the drainage trench is at least ten feet long, and ispreferably at least twenty feet long. The drainage trench may be lined,or it may be unlined.

It is also to be appreciated that the synthetic pieces of the presentinvention may be used with virtually any inside waterproofing systemand/or method. For example, the synthetic rocks may be used alone, orthey may be used in conjunction with cove molds, or with rounded,slotted, perforated, or filtered, channels or tiles. They may be usedwith baseboards, above grade, below grade, compacted, or loose. Thesynthetic rocks may be used in any manner in which standard gravel,limestone or river-gravel would be utilized in a water-control orwaterproofing method.

It is also to be appreciated that the synthetic pieces of the presentinvention may be used with virtually any outside waterproofing systemand/or method. Here too, the pieces may be installed alone or inconjunction with other methods, such as cove molds, tiles, rounded,slotted, perforated, filtered, channels, baseboards, above grade, belowgrade, compacted or loose. The synthetic pieces may be used wherever anystandard gravel, limestone or river-gravel would be utilized in anoutside water-control or waterproofing method.

It is also to be appreciated that the synthetic pieces of the presentinvention may be used with virtually any sub-grade French drainingsystem in fields, yards, playgrounds, golf courses, farmland and/oracreage, etc. The inventive pieces and methods may also be used in anyerosion-control system, above surface or subsurface, alone or inconjunction with other water-control or waterproofing products and/ormaterials.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatall changes and modifications that come within the spirit of theinvention are desired to be protected.

1-16. (canceled)
 17. A method of preventing water from seeping upthrough the floor of the lower level of a building, said methodcomprising: a) providing a trench below the level of the floor of abuilding; b) at least partially filling in said trench with a pluralityof synthetic mini-tubes having a largest dimension of between about 0.5inches and about 3.0 inches; and c) providing a solid flooring materialover said synthetic mini-tubes to substantially cover said trench. 18.The method of claim 17 wherein at least some of said synthetic minitubes are contained in a mesh bag to facilitate placement of the pieces.19. The method of claim 17, and further including providing perforatedor slotted drain tile in said trench to facilitate draining water fromthe building.
 20. The method of claim 17 wherein said mini-tubes have aspecific gravity that is less than 3.0.
 21. The method of claim 17wherein said synthetic rocks have a specific gravity that is less than2.0.
 22. The method of claim 17 wherein said synthetic rocks have aspecific gravity that is less than 1.0.